JP2006098177A - Water leak detection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water leak detection system capable of detecting a water leak accurately. <P>SOLUTION: One mode of this water leak detection system is equipped with a water leak detection band 12 having a pair of mutually-insulated conductive wires, wherein each of the pair of conductive wires is exposed partially; and a water leak detector for detecting the water leak based on an electric resistance between the pair of conductive wires. In the system, a water absorbing member 22 having an electrolyte adhering thereto is disposed between a first exposure part 17 where a first conductive wire 13 is exposed and a second exposure part 18 where a second conductive wire 14 is exposed between the pair of conductive wires. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water leakage detection system, and more particularly to a water leakage detection system having a water leakage detection zone and a water leakage detector.

  A water leak detection system is used in a manufacturing factory of a display device such as a liquid crystal display device or an organic EL (ElectroLuminescence) display device or a manufacturing factory of a semiconductor device. This water leakage detection system detects that water leakage has occurred from each device in the manufacturing factory, and notifies the operator.

  In this water leakage detection system, a water leakage detection zone having two conductive wires is used to electrically detect water leakage. (For example, refer to Patent Document 1). The two conductive wires are insulated from each other by an insulating member. A part of each of the two conductive lines is exposed. When water leaks and the water leak detection zone is immersed in water, the exposed portion comes into contact with water. For example, a weak current of 3 mA or less flows between the two conductive wires through water, which is a conductive substance. Water leakage can be detected by amplifying this current and operating the relay. By installing this water leak detection zone on the floor, wall surface, under floor, etc., it is possible to detect water leak in the manufacturing factory.

Japanese Patent Laid-Open No. 5-187955

However, the conventional water leakage detection system has the following problems. In the above manufacturing plant, pure water may be used. Pure water generally has a higher specific resistance than normal water. Therefore, in the conventional water leakage detection system that electrically detects water leakage, water leakage may not be detected in the case of pure water having a conductivity of about 1.0 μS / cm or less. For example, in a typical leak detection system, the detectable resistance of the leak detector is about 0.1 MΩ. Since the electrical resistance when pure water leaks is about 0.4 MΩ or more, there is a case where sufficient current does not flow between the conductive wires and the water leak cannot be detected.
This invention is made | formed in view of such a problem, and it aims at providing the water leak detection system which can detect a water leak correctly.

  The water leakage detection system according to the first aspect of the present invention has a pair of conductive wires insulated from each other, and each of the pair of conductive wires is exposed at least partially, and the pair of conductive wires. A leak detection system comprising a leak detector for detecting leak based on flowing between an electrode pair, wherein the first exposed portion of the pair of conductive wires is exposed. And a second exposed portion at which the second conductive wire is exposed, a water absorbing member that exhibits conductivity when a water retention state is reached is disposed. Thereby, water leakage can be detected accurately.

  A water leakage detection system according to a second aspect of the present invention is the above-described water leakage detection system, wherein the water absorbing member includes an electrolyte. Thereby, water leakage can be detected accurately.

  A water leakage detection system according to a third aspect of the present invention is the above-described water leakage detection system, wherein the first electrode connected to the first conductive line through the first exposed portion, and the second A second electrode connected to the second conductive line via an exposed portion, and the water absorbing member is disposed from the first electrode to the second electrode. is there. Thereby, it is possible to accurately detect water leakage with a simple configuration.

  The water leakage detection system according to a fourth aspect of the present invention is the water leakage detection system described above, further comprising electrodes provided at positions corresponding to the first exposed portion and the second exposed portion, respectively, and the water absorbing member. The water-absorbing member is fixed by the electrode so as to be in contact with the first conductive wire and the second conductive wire. Thereby, it is possible to accurately detect water leakage with a simple configuration.

  According to the present invention, water leakage can be accurately detected. In particular, it is possible to provide a water leakage detection system capable of detecting leakage of pure water having an electrical conductivity of 0.1 μS / cm or less.

  Hereinafter, embodiments to which the present invention can be applied will be described. The following description is to describe the embodiment of the present invention, and the present invention is not limited to the following embodiment. For clarity of explanation, the following description is omitted and simplified as appropriate. Further, those skilled in the art will be able to easily change, add, and convert each element of the following embodiments within the scope of the present invention. In addition, what attached | subjected the same code | symbol in each figure has shown the same element, and abbreviate | omits description suitably.

  A water leakage detection system according to the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view schematically showing a configuration of a water leakage detection system according to the present invention. 10 is a water leakage detection system, 11 is an electrode, 12 is a water leakage detection zone, 13 is a first conductive wire, and 14 is a second Conductive wires, 16 is an insulating member, 17 is a first exposed portion, 18 is a second exposed portion, and 21 is a water leak detector.

  The water leakage detection system 10 includes a water leakage detector 21 and a water leakage detection zone 12 connected to the water leakage detector 21. The water leakage detection band 12 includes a first conductive wire 13 and a second conductive wire 14 and an insulating member 16 covering them. The first conductive wire 13 and the second conductive wire 14 are made of, for example, stainless steel, and the insulating member 16 is made of, for example, transparent soft vinyl chloride. The first conductive line 13 and the second conductive line 14 are insulated from each other by an insulating member. That is, as shown in FIG. 1, the insulating member 16 has an 8-shaped cross section, in which the first conductive line 13 and the second conductive line 14 having a circular cross section are disposed. The width of the water leakage detection zone 12 is about 8 mm.

  A plurality of electrodes 11 are attached to the water leakage detection zone 12. In a portion corresponding to the electrode 11, a part of the insulating member 16 of the water leakage detection band 12 is removed, and a part of the first conductive line 13 or the second conductive line 14 is exposed. The portion where the first conductive line 13 is exposed is referred to as a first exposed portion 17, and the portion where the second conductive line 14 is exposed is referred to as a second exposed portion 18. In FIG. 1, the first exposed portion 17 and the second exposed portion 18 are indicated by triangles having different directions for clarity of explanation. Then, the first conductive line 13 and the second conductive line 14 are electrically connected to the electrode 11 through the first exposed part 17 and the second exposed part 18, respectively.

  Next to the electrode 11 corresponding to the first exposed portion 17, the electrode 11 corresponding to the second exposed portion 18 is disposed. That is, the first exposed portions 17 and the second exposed portions 18 are alternately provided for the pair of electrodes 11. The electrode 11 corresponding to the first exposed portion 17 and the electrode 11 corresponding to the second exposed portion 18 form an electrode pair. The distance between the electrodes 11 in one electrode pair is about 25 mm. The electrode pairs are installed at intervals of about 333 mm. That is, the interval between adjacent electrode pairs is about 333 mm.

  This water leak detection zone 12 is connected to a water leak detector 21. For example, the water leakage detector 21 applies a voltage between the first conductive wire 13 and the second conductive wire 14 and measures the current flowing between them. And the water leak is detected based on the electric current which flows between conductive wires. That is, when there is no water leakage, since the first conductive line 13 and the second conductive line 14 are insulated, the current flowing between the first conductive line 13 and the second conductive line 14 is substantially 0. On the other hand, when the water leaks, the electrode pair is submerged, so that the current flowing between the first conductive line 13 and the second conductive line 14 increases according to the electrical resistance of the water. Thus, the water leak detector 21 detects water leak between the first conductive wire 13 and the second conductive wire 14 based on the electrical resistance. For example, when the electrode 11 connected to the first conductive wire 13 and the electrode 11 connected to the second conductive wire 14 are immersed in water, about 3 mA is passed through the water which is a conductive substance. The following current flows. Water leakage is detected by amplifying this current and operating the relay.

  However, when pure water having an electrical conductivity of 1.0 μS / cm or less leaks, there is no sufficient change in electric resistance, so that no detectable current flows between the electrodes. In the present invention, when pure water with low conductivity leaks, a water absorbing member is disposed between the electrode pair in order to detect water leakage. The structure of this water absorbing member will be described with reference to FIGS.

  FIG. 2 is a diagram schematically showing the configuration of the water absorbing member and the electrode. FIG. 3 is a cross-sectional view schematically showing the configuration of the water absorbing member and the electrode. As the water absorbing member 22, for example, a duster (trade name) to which dirt is attached can be used. More specifically, a dasper to which an electrolyte is added is used as the water absorbing member 22. The water absorbing member 22 is provided between the electrode 11 corresponding to the first exposed portion 17 and the electrode 11 corresponding to the second exposed portion 18. That is, the water absorbing member 22 connects the electrode 11 corresponding to the first exposed portion 17 and the electrode 11 corresponding to the second exposed portion 18. As shown in FIG. 3, the water absorbing member 22 is wound around the electrode 11 and attached to the electrode 11. As the water absorbing member 22, an insulating member is used in a state where water is not retained.

  By providing the water absorbing member 22 between the first exposed portion 17 and the second exposed portion in this way, even if pure water having a conductivity of 1.0 μS / cm or less leaks, It can be detected accurately. That is, when the water absorbing member 22 is immersed in water, the water absorbing member 22 retains water. At this time, the electrolyte adhering to the water absorbing member 22 is dissolved in water. When the electrolyte is dissolved in water, the resistance between the electrode pair becomes lower than when the water absorbing member 22 is not provided. That is, the water in which the electrolyte is dissolved has a lower resistance than pure water. Thereby, the electric current which flows between electrode pairs increases, and the water leak detector 21 can detect water leak reliably.

  In FIG. 3, the water absorbing member 22 is wound around and fixed to the outer periphery of the electrode 11. However, the conductive wires 13 and 14 and the water absorbing member 22 may be brought into contact with each other. This example will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a configuration in which the water absorbing member 22 and the electrode 11 are brought into contact with each other. FIG. 4 shows a cross-sectional view of the water leakage detection zone 12 and the electrode 11 in the first exposed portion 17.

  In the example shown in FIG. 4, the first conductive wire 13 and the second conductive wire 14 are directly connected to the water absorbing member 22. The water absorbing member 22 is fixed by the U-shaped electrode 11 so as to be in contact with the first conductive wire 13 at the first exposed portion 17. As shown in FIG. 2, the water absorbing member 22 is disposed between the first exposed portion 17 and the second exposed portion 18. Similar to the configuration shown in FIG. 4, the second conductive wire 14 is fixed so as to contact the water absorbing member 22 at the second exposed portion 18. Therefore, the first conductive wire 13 and the second conductive wire 14 are connected via the water absorbing member 22. For example, the water absorbing member 22 is attached to the inside of the U-shaped electrode 11. Then, the electrode 11 is slid from the side and fitted to the water leakage detection zone 12. Thereby, in the exposed part of the water leak detection zone 12, the water absorbing member 22 is fixed so that the conductive wire and the water absorbing member 22 are in contact with each other.

  As the water absorbing member 22, an insulating member is used in a state where water is not retained. As the water absorbing member 22, a resin or cloth that has insulating properties in a state where water is not retained and conductivity is exhibited in a state where water is retained can be used in addition to daspar. By using such a water absorbing member 22, the resistance when water is retained is lower than the resistance with pure water. Therefore, the current flowing between the conductive wires increases, and the water leakage detector 21 can accurately detect water leakage.

  In the present invention, for the water absorbing member 22, for example, an industrial wiper such as Kim Towel (trade name) or Dasper can be used. In particular, Kim towel is a non-woven fabric of water-impregnated fiber, the raw material is pulp, and sodium hydroxide or sulfate which is an electrolyte is used in the production process. For this reason, trace amounts of sodium hydroxide, sulfate, etc. remain in the fiber of Kim Towel. Also as this electrolyte, sodium hydroxide or sulfate dissolves and exhibits electrical conductivity when pure water is retained. Thereby, the leakage of pure water can be easily detected. Moreover, it is also possible to use as the water absorbing member 22 what is adhered by spraying an electrolyte such as sodium hydroxide, water-soluble sulfate or sulfite on a cloth (water-immersed member) of water-soluble fiber such as cellulose. It is.

  An example of use of this water leakage detection system will be described with reference to FIG. FIG. 5 is a diagram schematically showing a display device manufacturing factory using the water leakage detection system. Reference numeral 40 denotes a manufacturing factory, 41 denotes a thermostatic bath, and 42 denotes an electrode pair.

  In the manufacturing factory 40 shown in FIG. 5, a plurality of thermostatic baths 41 using pure water are provided. Electrode pairs 42 are respectively disposed on the floor surface of the manufacturing factory 40 at positions corresponding to the constant temperature bath 41. As shown in FIG. 2, the electrode pair 42 includes two electrodes 11 including an electrode 11 corresponding to the first exposed portion 17 and an electrode 11 corresponding to the second exposed portion 18. The electrode pair 42 is disposed at a distance of about 0.3 mm from the adjacent electrode pair. The total length of the water leakage detection zone 12 was 15 m. Such an electrode pair 42 is arranged on the floor. As a result, it was possible to accurately detect leaks of pure water and to detect a wide range of leaks.

  The above-described water leakage detection system is suitable for detecting leakage of pure water having a high specific resistance, that is, low conductivity. By using such a water leakage detection system in a display device manufacturing factory or a semiconductor manufacturing apparatus manufacturing factory, it is possible to detect leakage of pure water at an early stage. Thereby, the secondary trouble after water leakage, for example, malfunction of a leak or a fire alarm, can be prevented.

It is a figure which shows typically the structure of the water leak detection system concerning this invention. It is a figure which shows typically the structure between the electrodes in the water leak detection system concerning this invention. It is sectional drawing which shows typically the structure of the electrode and water absorption member in the water leak detection system concerning this invention. It is sectional drawing which shows typically another structure of the electrode and water absorption member in the water leak detection system concerning this invention. It is a figure which shows typically the usage example of the water leak detection system concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Water leak detection system 11 Electrode 12 Water leak detection zone 13 1st conductive wire 14 2nd conductive wire 16 Insulating member 17 1st exposed part 18 2nd exposed part 21 Water leak detector 22 Water absorbing member 40 Factory 41 Constant temperature Tank 42 Electrode pair

Claims (4)

A pair of conductive wires insulated from each other, and each of the pair of conductive wires is exposed at least in part,
A water leakage detection system comprising a water leakage detector that detects water leakage based on a current flowing between the pair of conductive wires,
Of the pair of conductive lines, a water retention state is achieved between the first exposed portion where the first conductive line is exposed and the second exposed portion where the second conductive line is exposed. A water leakage detection system having a water absorbing member that sometimes exhibits conductivity.   The water leakage detection system according to claim 1, wherein the water absorbing member includes an electrolyte. A first electrode electrically connected to the first conductive line through the first exposed portion;
A second electrode electrically connected to the second conductive line through the second exposed portion;
The water leakage detection system according to claim 1 or 2, wherein the water absorbing member is disposed from the first electrode to the second electrode. Electrodes further provided at positions corresponding to the first exposed portion and the second exposed portion,
The water leakage detection system according to claim 1 or 2, wherein the water absorbing member is fixed by the electrode so that the water absorbing member is in contact with the first conductive wire and the second conductive wire.

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